It is known to sell hearing systems as a set of two or more devices, which are specifically tailored so as to be compatible and adapted to each other. If another device shall be added to the hearing system, that other device has to be such a specifically tailored device, too. This way, it is ensured that the hearing system as a whole functions correctly.
If hearing systems with different ranges of functionalities, e.g., basic hearing systems which offer only basic functionalities, advanced hearing systems which offer additional functionalities and high-end hearing systems which offer very many and very elaborate functionalities, shall be offered, it will usually be necessary to offer three distinct sets of devices: a first set of devices, which can be used in said basic hearing systems (and—at least in part—not usable in advanced or high-end hearing systems), a second set of devices, which can be used in said advanced hearing systems (and—at least in part—not usable in basic or high-end hearing systems), and a third set of devices, which can be used in said high-end hearing systems (and—at least in part—not usable in basic or advanced hearing systems). From an economical point of view and with respect to handling and logistics of the devices, this is not desirable.
It is desirable to find ways to provide devices which are usable in an increased number of hearing systems.